1. Field of the Invention
The present invention relates to a rotary electric machine integrated with a control device, which is integrated with a control device that performs driving control of a rotary electric machine and, more particularly, relates to a cooling structure of a stator current switching circuit section.
2. Description of the Related Art
As an example of a hitherto known rotary electric machine integrated with a control device, there is one shown in Japanese Unexamined Patent Publication No. 2007-228641. According to Japanese Unexamined Patent Publication No. 2007-228641, in a power rotary electric machine integrated with a control device including a power circuit section and a control circuit section, the control circuit section is disposed at a position where the power circuit section is not usually disposed when seen from a rotational axis direction so that the control circuit section does not block a flow of air for cooling the power circuit section and is radially outwardly shifted so as to eliminate overlap with a rotational position detecting sensor when seen from the rotational axis direction; and accordingly, cooling performance is improved.
According to the above mentioned known art, there are the following problems:    (1) Of three phase heat sinks for stator current switching circuit sections, a heat sink disposed in the midst rises to a higher temperature than that of other phase by heat transferring from both side heat sinks, and therefore, there is concern that only duration of life of a middle phase switching element is shortened;    (2) Furthermore, a heat sink disposed at a position close to a cylinder block of an engine is difficult to exhaust cooling air, because the heat sink receives heat from the cylinder block and the cylinder block is located at an outlet of the cooling air, and therefore, the heat sink is less inferior in cooling properties than other heat sink, and there is concern that only duration of life of a switching element of a phase close to the cylinder block is shortened; and    (3) Besides, there is a case where an area of an exhaust hole for cooling air is influenced by a bracket mounting pad, and the area of the exhaust hole close to the bracket mounting pad becomes small; and therefore, temperature of a heat sink of a phase in which the exhaust hole is small rises to a higher temperature than that of other phase heat sink, and there is concern that only duration of life of a switching element of the temperature-risen phase is shortened.